Life cycle of Phoebemima ensifera Tippmann (Coleoptera, Cerambycidae)

Life cycle of Phoebemima ensifera Tippmann Life cycle of Phoebemima ensifera Tippmann (Coleoptera, Cerambycidae) 287 Robin O. S. Clarke1 & Sonia Zamalloa1 1 Hotel Flora and Fauna, Casilla 2097, Santa Cruz de la Sierra, Bolivia. ABSTRACT. Life cycle of Phoebemima ensifera Tippmann (Coleoptera, Cerambycidae). An account of host plant selection, larval development and behaviour, and behaviour of adult Phoebemima ensifera. Illustrations of the host plant, plant parts, larva, pupa, and adult are provided. KEYWORDS. Biology; ethology; Hemilophini; Lamiinae. RESUMO. Ciclo vital de Phoebemima ensifera Tippmann (Coleoptera, Cerambycidae). Descreve-se a seleção da planta hospedeira, desenvolvimento e comportamento larval, e comportamento do adulto de Phoebemima ensifera. Ilustrações da planta-hospedeira, larva, pupa e adultos são fornecidas. PALAVRAS-CHAVE. Biologia; etologia; Hemilophini; Lamiinae. Monné & Hovore (2006) have recorded the Western Hemisphere tribe Hemilophini Thomson, 1868 from Kansas State, USA to Argentina. However, it is primarily a Neotropical tribe: three genera (five species) recorded from the USA (Kansas, South Carolina to Florida), 16 genera (36 species) from Mexico, 45 genera (110 species) from Central America, five genera (23 species) from the Caribbean, and 99 genera (333 species) from South America (of which eigth genera and 17 species have been recorded from Uruguay and Argentina, and none from Chile). Given that tribe the Hemilophini contains a multitude of species (nearly 500) with a large geographical range the knowledge of their biology and host plants is very limited. The first record, Bondar (1938), briefly outlines the damage done by the larva of Gagarinia borgmeieri (Bondar,1938); the second, Molinari (1942), gives a short account of the biology of Apagomerella versicolor (Boheman,1859). Duffy (1960) in his monograph of the immature stages of the Neotropical Cerambycidae further references the host plants of two species of Phoebe Audinet-Serville, 1835. Di Iorio et al. (1998) refer to the larval activity of Zeale nigromaculatata (Klug, 1829). Most recently, Monné (2002), catalogues the present knowledge with references to the host plants of three further species: Adesmus nevisi (Gounelle, 1909), Calocosmus speciosus Chevrolat, 1862, and Eranina argentina (Bruch, 1911). Based on observations of host plants, immatures and adults in the field and laboratory we describe, for the first time, the life cycle of Phoebemima ensifera Tippmann, 1960. Photographs of the host plant, girdled branches, larva, pupa, and adults are given. The acronyms used in the text are as follows: Museu de Zoologia, Universidade de São Paulo, São Paulo, Brasil (MZSP); Robin Clarke/Sonia Zamalloa private collection, Hotel Flora & Fauna, Buena Vista, Santa Cruz, Bolivia (RCSZ). MATERIAL AND METHODS The study was undertaken in Bolivia, Department of Santa Cruz, at the Hotel Flora & Fauna, 17°29’96"S/63°39’13"W, 430m, 5 km SE of Buena Vista. This hilly locality lies in disturbed transition forest (Semideciduous Chiquitano Forest and Tropical Humid Forest), 16 km from the foot of the eastern Cordillera of the Andes. Clarke & Sagot (1996) state that: “meteorological stations have only recently [1991] been established in the area and the data should be considered, only, as a guide to climate conditions.” They briefly outline the climate of this tropical locality, which is summarised as follows: “near enough to the equator to be little affected by day length (one hour’s difference), but far enough south to experience marked seasonal changes. The warm, austral summer [minimummaximum temperature 22-28°C] commences in September and ends in February, but not until December to February [mean maximum rainfall 1,258 mm] do rains reach their peak. The cooler, austral winter [minimum-maximum temperature 16-27°C] begins in March and ends in August, during which rainfall [mean maximum rainfall 224 mm] is considerably reduced.” In December 2004, two small sections of branch were found lying on the ground beneath a mature tree of Pithecillobium scalare Griseb. (family Mimosaceae). The ends of both sections appeared to have been severed from the inside; by inference, cut by a larva. One piece of branch was retained for further observation. Almost exactly a year later (8th December 2005) a cerambycid emerged, Phoebemima ensifera, of the tribe Hemilophini. Girdling has been referred to by Linsley (1961): “A very characteristic mode of feeding is found among the twig girdlers and pruners .... the twig is girdled by the adult beetles ... or by the larva of many of the Elaphidionini.” Regular visits were made to the Pithecillobium without Revista Brasileira de Entomologia 53(2): 287–290, junho 2009 288 Clarke & Zamalloa finding, what we now knew to be, further pupal chambers. However, on 11th January 2006 another species of Mimosaceae [Samanea tubulosa (Benth.), known locally as “Penoco”] was found with a girdled branch and on the ground a pupal chamber similar to that cut by P. ensifera. Forty-five weeks later (23rd November 2006) an adult of this species emerged from it. From January 2006 to September 2007 we have made observations of host plants in the field, and longitudinally sectioned branch parts and pupal chambers containing live larvae and pupae (kept in plastic vivaria) under simple (some humidity control) laboratory conditions. Using the data collected from 18 cases of girdled Samanea branches the following outline of the life cycle of Phoebemima ensifera is presented, together with photographs of the host plant, girdled branches, larva, pupa, and adults. 1 Material examined. Bolivia, Department of Santa Cruz, Hotel Flora & Fauna, 17°29’96"S/63°39’13"W, 430m, 5 km SE of Buena Vista. 1 female, 8.XII.2005, R. Clarke/S. Zamalloa col., emerged from internally girdled “Juno” branch (MZSP). The following with same data, different host plant: 1 female, 23.XI.2006, emerged from “Penoco” branch, first cut 11.I.2006, second cut 15.I.2006 (RCSZ); 1 female, 7.II.2007, emerged from “Penoco” branch, first cut 13.III.2006, second cut 16.III.2006 (RCSZ); 1 fifth instar larva, 1.VI.2007, from pupal chamber (6 cm long x 1,9 cm diameter) on ground below “Penoco” sapling, photographed and preserved in alcohol (MZSP); 1 pupa, 28.VIII.2007, from pupal chamber (7,0 x 1,7 cm.) on ground below “Penoco” sapling, 11.VII.2007, photographed and preserved in alcohol (MZSP). RESULTS Adult Behaviour. Adults come to light in October and November; three examples bred from cut branches kept under laboratory conditions emerged in November (2006), December (2005), and February (2007). It is probable that mating and oviposition take place shortly after emergence. All the Samanea selected for oviposition were small 2-3 metre-high plants (Fig. 1); albeit mature trees offered a multitude of branches of equal size, none had been girdled. Branches that were longitudinally sectioned indicated the absence of competi (...truncated)